Bifurcation of the fourth rib as a possible indicator of Gorlin’s syndrome in an 85-year-old female cadaver

Introduction Anatomical variations of human ribs have been well documented [1–3]. Common variations include asymmetric ribs, cervical or lumbar ribs, fusion of rib 1 and 2 and the absence of rib 1 [2, 3]. Unusual variants include fibrous tissue replacing costal cartilage, ribs bifurcated at the sternal insertion, two adjacent ribs articulating at their costal cartilages by a diarthrosis, synarthrosis or sydesmosis, the concurrent presence of cervical and lumbar ribs and the presence of coccygeal ribs [1]. The prevalence of rib variations has been reported to be between .04 and 14% with bifurcated ribs reported as the least common and cervical ribs as the most common [1, 2]. In another study of 47 patients with identified rib variations, the most common variant was fusion (72%), followed by bifurcation (28%) and hypoplastic ribs (26%). Vertebral variations associated with the identified rib were found in 72% of the patients [4]. The purpose of this case report is to describe a rare anatomical bifurcation in the right 4th rib in a female cadaver found during routine dissection and discuss possible underlying causes for this variant based other characteristics found in the donor. We conclude that the rib bifurcation seen in the current case combined with of other potential indicators including renal cysts and a history of brain tumors may indicate the presence of Gorlin’s Syndrome in this donor.